ETL testing confirms that the data we have extracted, transformed, and loaded has been extracted completely, transferred properly, and loaded into the new system in the correct format. Testing can also help identify and prevent issues with data quality during the ETL process, such as duplicate data or data loss.

Why do we need ETL Testing?

ETL testing is done to ensure that the data that has been loaded from a source to the destination after business transformation is accurate. It also involves the verification of data at various middle stages that are being used between source and destination. ETL stands for Extract-Transform-Load.

What is needed for ETL Testing?

Eight stages of the ETL testing process Identify business requirements — Design the data model, define business flow, and assess reporting needs based on client expectations. … Validate data sources — Perform a data count check and verify that the table and column data type meets specifications of the data model.